Surprise! It's Horace! Colum is on the road all day. I know, because they just stopped in to visit Frannie and me at the beach house, and then they were heading to dinner, and then they had another several hours to go before they reached their destination. So I thought I'd step in. I suppose it would have been nicer if I had thought of doing so at 7:30, when I first did the puzzle, but, well, I didn't.
Anywho, I liked this one quite a bit. SPLITSVILLE (17A: Where a rocky relationship may end) and AREYOUBLIND (57A: Angry shout to an umpire) are good anchors in the NW and SE, but I like to think PUTPENTOPAPER (34A: Begin writing) was the seed entry here. How could it not have been, I suppose? STEAMBOAT (10D: Setting for the first Mickey Mouse cartoon) and SPACERACE (32D: It was launched with Sputnik) were a little easy for a Friday, but perhaps that's just for "solvers of a certain age," like me.
With VLO in place, I dropped reVLOn right in, but no, it was something much more entertaining - PAVLOV. I salivate for good clueing like that... too much? And I loved seeing RETRONYM (38D: "Rotary phone," for one), LUMMOX (44D: Stumblebum), SCORPIO (22D: One who arrives around Halloween), and other excellent fill. And is the NUTPINE where pine nuts come from?
Really, everywhere you look there's quality material here: GASBAGS, GUFF, PIGLET, SKUNK, EMPORIUM, VAGABONDS ... so good.
OK, Colum, if you have anything more to say, speak up now, or forever stay in the comments!